driving home on the freeway andshe goes pop pop ....

[jonszr1]

does an few backfires when trying to get on the gas . so i get scared and just cruize her home once i get to my driveway which is abour 1 mile long i get on her a little to see what gives and she runs fine . pulled the plugs and they are fine . no ck engine light. so wtf . anyone ver have this happen to them ? she seems fine now but as you might understand its in my head . any ideas ????

 

[boomdriver]

does an few backfires when trying to get on the gas . so i get scared and just cruize her home once i get to my driveway which is abour 1 mile long i get on her a little to see what gives and she runs fine . pulled the plugs and they are fine . no ck engine light. so wtf . anyone ver have this happen to them ? she seems fine now but as you might understand its in my head . any ideas ????

I'd check the fuel pressure for flow at driving speed...clogging filters will do the burp and stumble, and be fine after the car sits for awhile and the crud settles. Next start up may be ok for days until the filter gets so full of trash that its just full and barely passes enough to allow an idle.

 

[jonszr1]

thanx for the input . thinking about it you are most likely right .i usually never let the tank get below 1/2 full before filling up ,but today being in ahurry let her get down to 3 bars before filling and on the way home is when it happened . i think it time to pull and drain the tank and flush the whole system . thank you for jogging this old guys memory

 

[boomdriver]

thanx for the input . thinking about it you are most likely right .i usually never let the tank get below 1/2 full before filling up ,but today being in ahurry let her get down to 3 bars before filling and on the way home is when it happened . i think it time to pull and drain the tank and flush the whole system . thank you for jogging this old guys memory

You're welcome !
old guys just have more memories to sort thru when a solution is needed!

It sounds like either filters or low fuel level sucking some air....same result, a drop in pressure that causes the engine to burp and stumble.

What I ended up doing with mine, was making a "well" for the pump assy to sit in after mopping the tank out.
The "well" is like a bucket that the pump lives in, thats about 6 to7" deep and has small holes in the rear bottom to equalize fuel level. The secret to the success of this home made fuel baffle system is the tank return line is also in the well, so its constantly being filled even while cornering. This "well" also tends to keep most of the heavier trash from getting to the pump sock since the sock is hidden inside the well.
The only real downside is the fact that when its empty, there's no sputtering and making it another couple miles....its EMPTY and quits pretty fast.

The OEM tank fuel baffle is just a little plastic tray glued to the tank bottom and they come off and float around sooner or later. They won;t do that new, but after a few yrs they all do because of that baffle coming loose. I guess the GM brand of JB weld just won;t hold forever..

I used a Lucas qt plastic bottle as my baffle....cut the top portion off, attached it to the pump assy so the float arm would clear, and stuck it in. The Lucas bottle contained petroleum product in it previously, so the plastic is compatable with fuel/oil. Thats been in there for a couple years now with no problems and no more starving for fuel below 1/2 tank and so far no filter issues.

 

[jonszr1]

wow great setup. i will have to do one to mine . is the gas tank hard to get out .it looks a little tight , a friend said i had to remove the rear valance to get it out .sure would be nice if one didnt have to do that. thanx again for sharing your solution

 

[boomdriver]

wow great setup. i will have to do one to mine . is the gas tank hard to get out .it looks a little tight , a friend said i had to remove the rear valance to get it out .sure would be nice if one didnt have to do that. thanx again for sharing your solution

Naw....tank removal is not necessary. Just go in thru the top. Pull the gas door panel (on top middle of tail on yours??) and that gives clear access to the semi square access panel in the tank. I think its 10-11 bolts, 10mm 1/2" then you can lift out the pump/level sender assy after disconnecting the hoses at the top.

If your Z has a 2 pump system it may be a different process, but I am certain it can be done, somehow.
Basically its a bucket that the pumps sit in so fuel cannot slosh away when low or when cornering when the tanks low. Mine is a little less than a qt capacity and I have not had any starvation issues until its totally empty...

I also placed holes in the bottom of the 'well' so fuel could flow in/out and equalize the level. I placed those at the rear or back of the well/bottle so that side loads would not force fuel out. I also cut a thin slot for the pump screen to stick thru and lay flat as it should. About 2/3 of the screen is inside the well with a inch sticking thru outside. Any fuel that moves thru that slot has to go thru the screen, and the holes in the rear of the well are small (1/8") just enough for liquid to flow and not big enough to have the trash circulate thru there.

If your Z has different access to the fuel pump, then I don;t know exactly what the details would be, but the principle remains the same.


Heres a pic of your 2 pump system....its similar to my sender/pump but a little larger. you might need a more square container to use as a 'well' so the float arm can clear.






I also used stainless wire to make attachments to avoid rust and still have some strength. Tie straps get brittle and break when submerged in gasoline. Your access to the pump assy is the same...removing the gas door panel. 4 torx screws and you;re there.

Just a fancy DIY tank baffle system with some intent.
Hope this helps.